Clock



FIG. 1 is a front elevational view of a clock showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a right side elevational view thereof, the left side being amirror image thereto;

FIG. 4 is a bottom plan view the top being a mirror image thereto.

The ornamental design for a clock, as shown and described.